The cover shows the crystal structure of the alanate NaAlH4

178 Pages·2004·7.24 MB·English

Cover Image:
The cover shows the crystal structure of the alanate NaAlH4,
a new class of hydrogen storage material. Al atoms are red, Na
atoms are green, and H atoms are blue. In this class of
materials, hydrogen “encapsulates” Al to form a hydrogen-rich
-
anion, AlH4 , whose structure resembles that of methane, CH4.
The alanate structure differs from that of the metal hydrides like
MgH2, where hydrogen is encapsulated by metal ions, and the
hydrogen density is correspondingly lower. In the cover image,
the diameter of the hydrogen atoms is enlarged to reflect the
very high scattering cross section of neutrons for hydrogen and
deuterium. This high sensitivity makes neutron scattering
a natural tool for probing the interaction of hydrogen with
materials. (In the report, see the sidebar, Using Neutrons to
“See” Hydrogen, on page 38).
Report prepared by Argonne National Laboratory. Argonne is a U.S. Department of Energy Office of
Science Laboratory operated by The University of Chicago under contract W-31-109-Eng-38.
Basic Research Needs for the Hydrogen Economy
Report on the Basic Energy Sciences Workshop
on
Hydrogen Production, Storage, and Use
Chair: Mildred Dresselhaus, Massachusetts Institute of Technology
Associate Chairs: George Crabtree, Argonne National Laboratory
Michelle Buchanan, Oak Ridge National Laboratory
Panel Chairs: Production Tom Mallouk, Pennsylvania State University
Laurie Mets, The University of Chicago
Storage Kathy Taylor, General Motors (retired)
Puru Jena, Virginia Commonwealth University
Fuel Cells Frank DiSalvo, Cornell University
Tom Zawodzinski, Case Western Reserve University
Office of Basic Energy Sciences Contact:
Harriet Kung, Basic Energy Sciences, U.S. Department of Energy
Special Assistance
Technical: Ian S. Anderson, Oak Ridge National Laboratory
Phil Britt, Oak Ridge National Laboratory
Larry Curtiss, Argonne National Laboratory
Jay Keller, Sandia National Laboratory
Romesh Kumar, Argonne National Laboratory
Wai Kwok, Argonne National Laboratory
John Taylor, Argonne National Laboratory
Administrative: Janice Allgood, Oak Ridge National Laboratory
Brenda Campbell, Oak Ridge National Laboratory
Karen Talamini, Basic Energy Sciences, U.S. Department of Energy
This report is available on the web at http://www.sc.doe.gov/bes/hydrogen.pdf.
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Second Printing, February 2004
Revisions
p 9, footnote 1: In terms of energy use, 1 gigawatt (GW) of power — the output of most light-
water nuclear reactors — corresponds to approximately 0.29 million tons/year (Mtons) of
hydrogen. One terawatt-year (TW-yr) of energy is equivalent to 0.29 gigatons (Gtons) of
hydrogen or 5.13 billion barrels (BB) of oil. The 3.3 TW use of fossil fuels in 2000 would thus
correspond to approximately 0.95 Gtons of hydrogen.
p 11, paragraph 2: Natural gas resources will be sufficient for several decades to expand this
capacity to support the FreedomCAR and Fuel Initiative. By 2040, it is anticipated that the use of
hydrogen in fuel cell powered cars and light trucks could replace consumption of 18.3 MB per
day of petroleum. Assuming that hydrogen powered vehicles have 2.5 times the energy
efficiency of improved gasoline vehicles, this reduction in petroleum use would require the
annual production of approximately 150 Mtons of hydrogen by 2040. If all of this hydrogen were
produced by petroleum reforming, the net savings in petroleum use would be 11 MB per day
(U.S. Department of Energy [DOE] 2003). The total energy used for transportation in the U.S.,
however, includes a substantial component of other kinds of vehicles (Figure 1a), and meeting
that need poses a greater challenge to hydrogen production.
p 12 (bottom) - p13 (top): The estimated power output from 10% efficient solar cells covering
1.7% of the land area of the U.S. (an area comparable to the land devoted to the nation's
highways) is 3.3 TW, equivalent to the total U.S. fossil fuel use in 2000.
The CD attached to the inside back cover contains low- and high-resolution PDFs of the report
and high-resolution files of the report graphics.
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PREFACE
Global energy consumption is expected to increase dramatically in the next decades, driven by
rising standards of living and a growing population worldwide. The increased need for more
energy will require enormous growth in energy generation capacity, more secure and diversified
energy sources, and a successful strategy to tame greenhouse gas emissions. Among the various
alternative energy strategies, building an energy infrastructure that uses hydrogen — the third
most abundant element on the earth’s surface — as the primary carrier that connects a host of
energy sources to diverse end uses may enable a secure and clean energy future for the Nation.
The Basic Energy Sciences (BES) Workshop on Hydrogen Production, Storage, and Use, held
May 13–15, 2003, was stimulated in part by an earlier study commissioned by the Basic Energy
Sciences Advisory Committee (BESAC) to assess the basic research needs to assure a secure
energy future. The charge to that study was to identify the fundamental scientific challenges of
the 21st century that “… Basic Energy Sciences must consider in addressing the [DOE] missions
in energy efficiency, renewable energy sources, improved use of fossil fuels, safe and publicly
acceptable nuclear energy, future energy sources, science-based stockpile stewardship, and
reduced environmental impact of energy production and use.” The study identified 10 basic
research directions in response to this charge, one of which was “Basic Research toward the
Hydrogen Economy.”1
In his State of the Union address in January 2003, President Bush unveiled the Administration’s
Hydrogen Fuel Initiative. The goals of this Initiative are to lessen America’s dependence on
imported oil and reduce greenhouse gas emissions. The President stated:
With a new national commitment our scientists and engineers will overcome
obstacles to taking these cars from laboratory to showroom, so that the first car
driven by a child born today could be powered by hydrogen and [be] pollution
free.
Inspired, in part, by the President’s announcement, and as a follow-on to the BESAC-sponsored
energy security study published in February 2003,1 BES established the present study on Basic
Research Needs for the Hydrogen Economy. The study was planned and executed in the period
from March to July 2003.
Prof. Mildred Dresselhaus of the Massachusetts Institute of Technology chaired the workshop,
and Drs. George Crabtree (Argonne National Laboratory) and Michelle Buchanan (Oak Ridge
National Laboratory) served as the Associate Chairs. The Associate Director of DOE’s Office of
Science, Basic Energy Sciences, Dr. Patricia M. Dehmer, challenged the workshop chair and
associate chairs to:
Identify fundamental research needs and opportunities in hydrogen production,
storage, and use, with a focus on new, emerging and scientifically challenging

1 “Basic Research Needs to Assure a Secure Energy Future,” A Report from the Basic Energy Sciences Advisory
Committee (Feb. 2003); available at http://www.sc.doe.gov/bes/besac/Basic_Research_Needs_To_Assure_A_
Secure_Energy_Future_FEB2003.pdf.
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areas that have the potential to have significant impact in science and
technologies. Highlighted areas will include improved and new materials and
processes for hydrogen generation and storage, and for future generations of fuel
cells for effective energy conversion.
Three panels were assembled to examine the charge in depth. Their topics and chairs were:
Basic Research Challenges for Hydrogen Production
Co-Chairs: Tom Mallouk (Pennsylvania State University)
Laurie Mets (The University of Chicago)
Basic Research Challenges for Hydrogen Storage
Co-Chairs: Kathy Taylor (General Motors, retired)
Puru Jena (Virginia Commonwealth University)
Basic Research Challenges for Fuel Cells and Novel Fuel Cell Materials
Co-Chairs: Frank DiSalvo (Cornell University)
Tom Zawodzinski (Case Western Reserve University)
Each panel was composed of about 15 panelists and 5 speakers with a broad spectrum of
expertise from universities, DOE national laboratories, and industry. The panelists and speakers
also included foreign experts, primarily from Japan and Europe. The names of the panel
members and speakers, as well as the agenda for the workshop, are provided in the appendix.
Four questions were posed to the panels:
• Where are we now?
• What do we already know?
• Where do we want to be?
• What do we need to do to get there?
To initiate answers to these four questions, program officers in the DOE Office of Energy
Efficiency and Renewable Energy (EERE) briefed each of the panels before the Workshop and
provided a multitude of reading materials. Mark Paster briefed participants on hydrogen
production and delivery, JoAnn Milliken on hydrogen storage, and Nancy Garland on fuel cell
activities under the FreedomCAR and Fuel Initiative. Harriet Kung served as the BES contact
throughout the study.
To set the stage for the Workshop, overview presentations were given. The panels carried out
their in-depth work from the evening of the first day through the morning of the third day. The
afternoon of the third day was devoted to oral reports of the findings of each panel, followed by
closing remarks.
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Millie Dresselhaus launched the Workshop with an overview presentation on its goals,
approaches, and framework. Pat Dehmer then gave a brief overview of BES, the background for
the Workshop, and her expectations. To broaden the perspective, a plenary session of five
speakers reviewed the present status of knowledge and the targets, requirements, and challenges
of various aspects of a hydrogen economy. Steven Chalk (DOE/EERE) addressed the Workshop
on the Administration’s FreedomCAR and Fuel Initiative by laying out the President’s vision, as
well as the plans and strategy of EERE in response to the Administration’s Initiative.
Specifically, a number of basic research areas in hydrogen production, storage, and fuel cells
were outlined for possible collaborations between EERE and BES. The potentially most vexing
problem, that of hydrogen storage, was reviewed in general by George Thomas (Sandia National
Laboratories, retired). He highlighted the many scientific and technical challenges of hydrogen
storage to enable hydrogen to be used as an energy carrier. Scott Jorgensen (General Motors)
gave the transportation industry’s perspective. He addressed hydrogen storage issues in vehicular
applications with special reference to the FreedomCAR targets and goals. Jae Edmonds (Pacific
Northwest National Laboratory) briefed the workshop participants on Hydrogen and Climate
Change, while Jay Keller (Sandia) presented the Science of Hydrogen Safety.
Following the plenary talks, the panel chairs reviewed the current status, summarized the
technology goals, and identified key fundamental scientific challenges for their panels, in the
context of the background provided by the pre-workshop briefings and plenary presentations.
A summary of the cross-cutting issues was presented, and Millie Dresselhaus and Pat Dehmer
made closing remarks.
This Workshop Report responds to the four research challenges for the hydrogen economy
outlined by Secretary of Energy Spencer Abraham in his address to the National Hydrogen
Association2:
• Dramatically lower the cost of fuel cells for transportation,
• Develop a diversity of sources for hydrogen production at energy costs
comparable to gasoline,
• Find viable methods of on-board storage of hydrogen for transportation uses,
and
• Develop a safe and effective infrastructure for seamless delivery of hydrogen
from production to storage to use.
The reports of the panels on hydrogen production, storage, and use in fuel cells and the high-
priority research directions identified by the Workshop address these research challenges.
The focus of the Workshop was to identify knowledge gaps in the scientific and technological
bases for hydrogen production, storage and use, and to identify high-priority fundamental
research directions that would likely have high impact on enabling a hydrogen economy. In

2 Secretary of Energy Spencer Abraham, address to the National Hydrogen Association (March 5, 2003); available
at http://energy.gov/engine/content.do?PUBLIC_ID=13384&BT_CODE=PR_SPEECHES&TT_CODE=PRESS
RELEASE.
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addition, the Workshop focused on identifying cross-cutting issues, whereby progress made in
one area would significantly impact other areas, thereby accelerating the overall progress of the
hydrogen initiative. The Workshop aimed primarily at defining bold new research directions to
address long-term “Grand Challenges,” as well as identifying intermediate-term “show-
stoppers.”
This Report is the result of a team effort by the panel chairs and Workshop chairs and is based on
the presentations and discussions, as well as input from panel members. The document
underwent a review process before release. Our intent is to issue a Report that accurately reflects
the current scientific and technological status of a potential hydrogen economy, as well as the
many great challenges that must be met for its successful implementation.
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CONTENTS
Preface..................................................................................................................................... iii
Executive Summary................................................................................................................ ix
Introduction and Overview..................................................................................................... 1
Reports of the Panels on Basic Research Needs for the Hydrogen Economy........................ 7
Basic Research Challenges for Hydrogen Production................................................ 9
Basic Research Challenges for Hydrogen Storage..................................................... 31
Basic Research Challenges for Fuel Cells and Novel Fuel Cell Materials................. 53
High-Priority Research Directions.......................................................................................... 79
Low-Cost and Efficient Solar Energy Production of Hydrogen................................. 81
Nanoscale Catalyst Design......................................................................................... 85
Biological, Biomimetic, and Bio-inspired Materials and Processes........................... 89
Complex Hydride Materials for Hydrogen Storage.................................................... 95
Nanostructured and Other Novel Hydrogen Storage Materials.................................. 99
Theory, Modeling, and Simulation of Materials and Molecular Processes................ 102
Low-Cost, Highly Active, Durable Cathodes for Low-Temperature Fuel Cells........ 108
Membranes and Separation Processes for Hydrogen Production and Fuel Cells....... 113
Analytical and Measurement Technologies................................................................ 117
Impact of the Hydrogen Economy on the Environment............................................. 120
Safety in the Hydrogen Economy............................................................................... 124
Cross-cutting Research Directions.......................................................................................... 129
Conclusions............................................................................................................................. 143
Appendix................................................................................................................................. 151
Workshop Program..................................................................................................... 153
Workshop Participants................................................................................................ 158
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